In general, a structure of an LCD display device having a glass substrate with retaining walls all around is shown in FIG. 1, as we can see when assembling a backlight structure, disposing a reflector plate 6 on one side of a light guide plate 4, disposing an optical membrane material 3 on the other side, disposing a frame body 5 outside the light guide plate 4a and the optical membrane material 3, disposing a shielding adhesive tape 2 above the frame body 5, the shielding adhesive tape 2 shielding the engagement location between the optical membrane material 3 and the frame body 5, and placing a glass substrate 1 above the shielding adhesive tape 2. In order to facilitate the assembling of the shielding adhesive tape 2, the glass substrate 1 and the reflector plate 6, retaining wall structures 51 as shown in FIG. 2 are disposed respectively above and below the frame body 5, so as to provide limit when placing the shielding adhesive tape 2, the glass substrate 1 and the reflector plate 6. The assembling of the backlight and the LCD display device is facilitated by adopting these retaining wall structures. If the LCD display device has an iron frame component, the retaining wall structures 51 also can be disposed on the iron frame component.
Currently, an important development trend of the LCD display device such as mobile phone, Tablet PC and TV are designed in narrow bezel, a common narrow bezel product is shown in FIG. 3, in which the length and width dimensions of the glass substrate 1 are slightly smaller than the length and width dimensions of the backlight comprised of the light guide plate 4 and the optical membrane material 3, the difference is normally about 0.1 mm, at this time, the retaining wall structures 51 can not be molded on the frame body 5, as shown in FIG 4.
However, the kind of narrow bezel product without retaining wall on the frame body needs to be assembled by auto line contraposition or using special fixture in the assembling process, which increases the complexity and the cost, but if adopting manual assembling , it has problems of low accuracy and high demand on the operator.